clickhouseSelect sumIf query example

SELECT sumIf(age, date < '2022-01-01') FROM tblctrl + cgithub

`sumIf` sum specified column value if expression is `true`	`age` name of the column to sum
`date < '2022-01-01'` expression to check (should we add this row value to the total sum)	`tbl` table to select data from

SELECT sumIf(age, date < '2022-01-01') FROM tbl

┌─sumIf(age, less(date, '2022-01-01'))─┐
│                                  125 │
└──────────────────────────────────────┘